<html>
<head><meta charset="utf-8"><title>Generic Associated Types dependent on Chalk? · wg-traits · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/index.html">wg-traits</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html">Generic Associated Types dependent on Chalk?</a></h3>

<hr>

<base href="https://rust-lang.zulipchat.com">

<head><link href="https://rust-lang.github.io/zulip_archive/style.css" rel="stylesheet"></head>

<a name="198958584"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198958584" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Carson Swoveland <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198958584">(May 27 2020 at 21:56)</a>:</h4>
<p>Looking to contribute to rustc and after asking a question related to the linked issue I was told to come here: It's possible that work on it is blocked in some way on work related to chalk? If it isn't I'll probably look into it some more.<br>
<a href="https://github.com/rust-lang/rust/issues/67510">https://github.com/rust-lang/rust/issues/67510</a></p>



<a name="198958695"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198958695" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198958695">(May 27 2020 at 21:57)</a>:</h4>
<p>So, long term GATs are more or less blocked on Chalk</p>



<a name="198958733"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198958733" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198958733">(May 27 2020 at 21:58)</a>:</h4>
<p>I think <em>maybe</em> <span class="user-mention" data-user-id="116009">@nikomatsakis</span> said he had an idea to unblock it in rustc, but I'm not sure</p>



<a name="198958861"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198958861" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Carson Swoveland <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198958861">(May 27 2020 at 21:59)</a>:</h4>
<p>Is it worthwhile even attempting to work on parsing/AST for them, then, or is the whole layout dependent on what happens in the future and it'd just be entirely obsolete?</p>



<a name="198958919"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198958919" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198958919">(May 27 2020 at 22:00)</a>:</h4>
<p>I think getting parsing/AST working is probably worthwhile</p>



<a name="198959013"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198959013" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198959013">(May 27 2020 at 22:00)</a>:</h4>
<p>you <em>could</em> even connect into the Chalk integration if you <em>really</em> wanted to (but I imagine you would probably run into issues)</p>



<a name="198959069"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198959069" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Jack Huey <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198959069">(May 27 2020 at 22:01)</a>:</h4>
<p>I'm not really the best person to answer questions on rustc though</p>



<a name="198959266"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198959266" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198959266">(May 27 2020 at 22:02)</a>:</h4>
<p>we already have parsing support etc</p>



<a name="198959292"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198959292" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198959292">(May 27 2020 at 22:03)</a>:</h4>
<p>that said, during the current sprint we are hoping to make progress on GATs in rustc</p>



<a name="198959392"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198959392" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Carson Swoveland <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198959392">(May 27 2020 at 22:04)</a>:</h4>
<p>Ah, well, then I suppose already having parsing support would solve the parsing support problem</p>



<a name="198990938"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198990938" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198990938">(May 28 2020 at 07:34)</a>:</h4>
<p>Wait, are we talking about rustc's parser or chalk's parser?</p>



<a name="198990975"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/198990975" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> detrumi <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#198990975">(May 28 2020 at 07:35)</a>:</h4>
<p>Because the code in <a href="https://github.com/rust-lang/rust/issues/67510">#67510</a> results in parse errors on nightly</p>



<a name="199007575"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/199007575" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Areredify <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#199007575">(May 28 2020 at 10:58)</a>:</h4>
<p>Last I checked it wasn't there</p>



<a name="199046876"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/199046876" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#199046876">(May 28 2020 at 16:36)</a>:</h4>
<p>Generic associated types in trait paths are not currently parsed, that's what <a href="https://github.com/rust-lang/rust/issues/67510">#67510</a>  is for.</p>



<a name="199047401"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/199047401" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#199047401">(May 28 2020 at 16:41)</a>:</h4>
<p>OK, my bad, though I think I was thinking more of <code>type Foo&lt;T&gt;</code> in a trait def'n when I said parsing worked</p>



<a name="199270038"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/144729-wg-traits/topic/Generic%20Associated%20Types%20dependent%20on%20Chalk%3F/near/199270038" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Carson Swoveland <a href="https://rust-lang.github.io/zulip_archive/stream/144729-wg-traits/topic/Generic.20Associated.20Types.20dependent.20on.20Chalk.3F.html#199270038">(May 30 2020 at 18:36)</a>:</h4>
<p>—So, it would be worthwhile to get some work done on that then?<br>
As best I can tell it seems that AST-wise the only addition is an optional <code>GenericArgs</code> on <code>AssocTyConstraint</code></p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
</html>